ellerbeck



Nov. 24, 1959 G. c. ELLERBECK 2,914,247

VALUE APPROXIMATION MECHANISM Filed Oct. 30. 1953 2 Sheets-Sheet 2 United States Patent O VALUE APPROXIMATION MECHAWISM Grant C. Ellerheck, San Leandro, Calif, assignor to Friden, Inc., a corporation of California Application October 30, 1953, Serial No. 389,376

7 Claims. (Cl. 235144) This invention relates to calculating machines and is concerned more particularly with the provision of an improved register clearing mechanism particularly adapted to reset preselected orders of the register toa predetermined value, such as It is a general object of my invention to provide an improved means for completing calculations in desired orders to the nearest cent, and to perform this operation .in such a Way that the total, or accumulated totals, will be correct to the nearest cent.

In many business calculations involving the multiplication of one value by another, one of the values is a fraction of a cent, so. that the product secured will be registered in fractions of a cent. One example of sub work is payroll calculations in which it is necessary to multiply a rate paid for the work by the number of hours work in order to obtain the amount to be paid to each employee, in which the rate may include a fraction of a cent. Another example is in billing operations in which the price per item will be given in fractions of a cent so that the total price to be paid will also include similar fractions. It is necessary to complete the calculation to the nearest cent, and it is very desirable that this be done automatically so as to avoid mental operations on the part of the calculating machine operator.

One of the most convenient ways of performing this rounding off operation to the nearest cent is to insert a value of 5 in the order next below the lowest desired value (for example, in the mills order in the examples cited above, i.e., in the order below the cent order) at the time of clearing the register. If the values added thereto are less than half a unit (five mills, or a half-cent, in the example suggested), the value in this lowest order will be no greater than "9 and no tenstransfer will occur into the next higher, or cents, order. On the other hand, if the value added to the 5 is more than 5, then the dial in the lowest, or mills, order will pass through the 9 to 0 position and will therefore initiate. a tens-transfer into the next higher, or cents, order. Thus, in rounding 01f to the closest cent by this method, if the mills accumulated are less than 5, the cents dial reads the accumulated number of cents, but if more than five mills are accumulated, those values added to the five mills initially inserted are effective to operate a tens-transfer into the cents order and thus register one cent more than the totals actually accumulated in that order. Thus, in either situation, the total is rounded off to the closest cent, automatically.

It is therefore a particular object of my invention to provide an improved mechanism for inserting the half cent, or five mills, in any one of a number of preselected orders of the calculating machine and thus accumulate values to the closest cent.

It is another object of my invention to provide a calculating machine in which the resetting operation serves to enter one or more half-cent, or other half-unit, values in selected orders of the accumulator.

' Another object of the present invention is to provide a resetting, or clearing, mechanism which will enter predetermined values, such as 5, in certain selected orders of the accumulator as part of the resetting or clearing operation.

A further and important object of the present invention is to provide a rounding off, or half-cent, mechanism which does not require a disabling of the tens-transfer devices which is usually necessary for such mechanisms.

These and other objects of the present invention will be apparent from the following description of a preferred embodiment thereof, as illustrated in the accompanying drawings in which:

Fig. 1 is a plan view of the right-hand portion of a register with which my invention can be associated, with the cover removed.

Fig. 2 is a plan View, similar to Fig. 1, with certain portions broken away to show various mechanisms of my invention.

Fig. 3 is an enlarged detail in cross section of the principal elements of my invention, taken along the plane indicated by the line 33 of Fig. 1.

Fig. 4 is an enlarged detail of the clearing mechanism associated with the register shown in Figs. 1 and 2.

I Fig. 5 is an enlarged front view of a portion of two of the accumulator dial shafts with which my invention is associated.

Fig. 6 is a plan view of the conventional stop cams and cooperating finger utilized in the preferred form of my invention, such as a view taken along the plane indicated by the lines 6-6 of Fig. 5.

Fig. 7 is a plan view of the upper stop cam and stop finger associated with my invention, such as a view taken along the plane indicated by the line 77 of Fig. 5.

My invention is illustrated as embodied in the accumulator register of the type shown and disclosed in the patent to Carl M. Friden of January 28, 1941, No. 2,229,889. Generally, such calculating machines include a selection mechanism, actuating means, and various control mechanisms for performing various operations, such as addition, subtraction, multiplication and division. Such mechanisms are assumed to be of the type particularly disclosed in the patent referred to, and, as such, are so well-known that their disclosure is not necessary to an understanding of the instant invention. Such machines generally include a shiftable carriage in which an ordinally arranged accumulator is mounted. In the patent referred to, the carriage includes a hollow frame bar 10, which is slidably mounted in the calculating machine and which can be moved to any preselected ordinal position by means not pertinent and not shown. A plurality of ordinally arranged accumulator dials 11 are rotatably mounted in the carriage frame it), as by mounting upon dial shafts 12 which are journalled in the top and bottom of the frame bar. The lower ends of the dial shafts 12 carry a driving gear, not shown, rigidly secured thereto, which gears are driven by the machine to accumulate values in the register dials 11. The register dials are conventionally centralized in a full-value position by a conventional centralizing means, not shown, and generally are provided with a tens-transfer mechanism which is of no interest in the present invention.

Means are provided for clearing the register dials 11 to 0 when desired. In my preferred embodiment, the clearing means comprises a pair of clearing racks 15 mounted for longitudinal movement in the interior of the frame bar 10, each of said racks including a plurality of series of rack teeth 14 sequentially arranged with respect to a land portion 22 and a relieved portion 13, as shown in Fig. 4. The edge of the land portion 22 extends to the full height of the teeth 14 and, when the rack is moved to its clearing position, lies opposite the respective multilated gear 16 and prevents its rotation;

while the relieved portion normally lies opposite the respective gear 16 and permits it to turn freely. The teeth and the lands and-reliefs of the racks are staggered on the two racks 15 so that they may cooperate with mutilated gears 16 mounted on the respective shifts 12, alternate mutilated clearing gears 16 being vertically, or axially, offset along the shafts 12 to permit one series of gears to be operated by one rack, and the other series to be operated by the other rack. Each such gear is mutilated, as shown in Figs. 2 and 4, and the mutilated portion is in the position shown in these figures when the associated dial stands at 0.

To perform the resetting, or clearing, operation, the racks 15 are. moved laterally of the machine (lengthwise of the carriage frame Such movement causes the toothed portions thereof to engage the clearing gears 16, which are displaced from the 0 position and rotate them, and their associated shafts and dials, to the 0 position. When the dial assembly reaches the 0 position, further rotation is blocked by a blocking means to be described shortly. It is conventional in machines of this kind, to provide various means for operating the clearing racks, such as the manually operated knob 17, shown in Fig. 1, which is mounted on post 18 rigidly mounted in the racks 15. The clearing racks may also be operated by a conventional power means, which .includes the power-operated bar 19 which acts through an interponent 20 rotatably mounted on the post 18. The interponent 20 is rotatable into, and out of, engagement with a pin 21 mounted on the power-clearing bar 19, whereby the clear racks 15 may be operated from the power-operated bar 19, or not, at the will of the operator. Conventionally, the power stroke of the racks is to the right, after which they are returned to the left by the force of a strong spring, not shown-the racks engaging the mutilated gears during the power stroke to the right to return them to the 0 position while the return stroke is an idle one. It is conventional in machines manufactured under the patent above-mentioned, tosplit the racks 15 into a right-hand portion and a lefthand portion, not shown, whereby either section or both can be cleared at the will of the operator, as determined by the setting of the necessary controls, and the operation of the power bar 19.

In order to insure stopping of the numeral wheels or dials at 0 without overthrow, a stop slide is slidably mounted upon the upper surface of the carriage frame 10. The conventional method of mounting the stop slide 25 on the frame bar 10 comprises a plurality of slots 23 in the slide embracing pins 24 mounted on the frame bar, as shown in Fig. 2. The stop slide is provided with a projection, or shoulder, 26 for each order of the accumulator, which shoulders, or fingers, are adapted to be moved into the path of travel of an abutment 28 formed on a stop cam 27, one of which is mounted on each of the dial shafts 12 immediately adjacent the upper surface of the frame 10. The stop slide 25- is moved in synchronism with the movement of the racks 15 by any suitable means. A conventional means normally used with the machine of the patent above-mentioned, comprises a stud 29 depending from a bracket 30 formed on the right-hand end of the power bar 19. lncidentally, the bracket 30 lies with a portion of its left side abutting the clearing post 18, whereby the power slide is moved to the right upon manual operation of the clearing mechanism, while the reverse is not necessarily true. A bellcrank 31 is pivotally mounted on the right-hand end of the frame 10 by any suitable means, such as screw 32. This bellcrank has a rightwardly extending arm 33 which is provided with a cam surface 34 engaging the stud 29. Thus, movement of the clearing bar 19 toward the right, which occurs at .the start of clearing operation, causes the stud 29 to engage the cam face 34 of the bellcrank, thereby rocking the bellcrank (clockwise in Fig. 2), and holding it in the 4 rocked position until the bar 19 returns to its inoperative position shown.

The rearwardly extending arm 35 of the bellcrank 31 is bifurcated, as at 36, to embrace a pin 37 rigidly secured to the right-hand end of the stop slide 25. Operation of the clear bar 19 thus causes the stud 29 to rock the bellcrank 31, which, through the pin-and-slot arrangement 37, 36, moves the stop slide 25 toward the right. in this position, the shoulders, or fingers, 26 lie in the path of travel of the abutments 28 so that when the respective shafts are rotated to their 0 position, the shoulders 28 abut against the end of the fingers 26, thereby blocking further rotation of the dial shafts 12.

The mechanism heretofore described is conventional and is not claimed herein. My invention comprises a mechanism operative with the conventional clearing mechanism, heretofore described, to insert a preselected value, such as 5, in selected orders, at the will of the operator. The mechanism of my invention is, in effect, supplemental to the conventional mechanism.

The mechanism of my invention, which is particularly adapted to return selected dials to a 5, or half-cent, position, will now be described. It can be mentioned that this mechanism is adapted, during the return stroke of the clearing racks 15, to rotate the dial 11 and shaft 12 sufliciently to cause the teeth of the mutilated gear 16 to engage the teeth of the associated clearing rack 15 during the return stroke of the rack. ment of the clearing gear and rack occurs when the rack has returned towards its home position a distance equivalent to five teeth of the rack 15. By this means, the gear 16, when rocked to engage the returning rack, can move five teeth spaces and therefore leave a 5 in the selected dial. Associated with the means for so returning the dials 11 to the 5 position, is a second stop bar, acting in an opposite direction from the first-men tioned stop rack slide 25, thereby stopping the dials in the 5 position and preventing overthrow thereof. By this method, the dials 11 are cleared backwards, in a subtractive direction, from their adjusted positions to 0, and then returned in the reversed direction to 5, whereby they never pass through the 9 to 0 position and therefore do not operate the tens-transfer mechanism between adjacent orders of the dials. By this means, I am enabled to avoid the complicated mechanism conventionally used to disable the tens-transfer mechanism during a clearing operation.

The mechanism for accomplishing the results just men tioned comprises a small pin, or projection, 77, preferably placed on the top of the dial 11, as shown in Fig. 1. This pin is placed in those dials on which the half-cent mechanism may be used by an operator, and in Fig. 1 is shown as being placed on each of the dials 11 of the lowest ten orders. Associated with the pins 77 are a plurality of operating arms 100. The operating arms are pivotally mounted on suitable posts 101 rigidly mounted in a transverse bar 102 that is attached to the rear of the carriage frame 10 by any suitable means, such as brackets 103. The arms 100 are provided with elongated slots 104 which embrace the posts 101 to permit longitudinal movement of the operating arms 100 as well as oscillation thereof.

. The arms 100 are biased to a forward position by suitable springs 105 tensioned between the lower end of the posts 101 and a stud 106 at the rear and lower face of the operating arms, as shown in Fig. 3.

The various posts 101 are provided with rotatable knobs 110, as shown in Figs. 1 and 3. The upper part of these knobs have a central bore 111, which preferably encloses a compression spring 112 seated on the interior end of the bore and the enlarged head 107 of the post, thus biasing the knob 1111 downwardly against the operating arm 100. The lower end of the knob 110 is provided with an external cam 113, which, as shown in Fig. 1, extends through an arc of nearly Cooperating with the cam 113, on each of the arms 100, is a stud 114, rigidly This engagesecured to the upper face of the arm. When the cam portion 113-1s rotated to the forward position, as shown in the extreme right-hand assembly in Fig. 1, the related operating arm 100 is urged to its forward position by the force of spring 105, in which position the nose 99 on the forward end of the arm 100 is adapted to engage the pin 77 on the first order dial 11. When, however, the cam 113 is rotated toward the rear, it engages the pin 114, forcing the related arrn 100 rearwardly against the force of spring 105 and thereby moving the related arm 100 rearwardly out of the position in which it can engage the pins 77 on the related dials (as shown in the second and third orders of Fig. l).

Inorder to hold the knob in either adjusted position, it preferably is provided with a bore at its lower end adapted to fit over a collar 115 on the post 101. The collar 115 is provided with a single pin, or stud, 116, which is adapted to engage one or the other of diametrically opposed bores 117 in the lower end of the knob 110, thereby holding the knob in either of the adjusted positions. The knob 110 can be rotated by the operator, when desired, by lifting the knob against the force of its spring 112, then rotatingthe knob until the other bore 117 seats over the stud 116. By this means the arms 100 can be #set by the operator, as desired, to either the forward position shown in the first order of Fig. l or to the rearward position shown in the second, third, fourth and tenth orders thereof.

Oscillation of the operating arms 100 can be secured by any one of a number of means which would be obvious to those skilled in the art. I show, in Fig. 1, a simple arrangement which is effective to rock the operating arms 100. In the mechanism shown in Fig. l, a slide 125 has an aperture, not shown, which fits over the post 1 8 of the clearing knob 17, so that the slide moves synchronously with movement of the knob 17. The left end of the slide is provided with an elongated slot 126 which embraces a screw stud 127 mounted on the clear operating bar 19. Thus, movement of the knob to the right will always reciprocate the side 125 synchronously with movement of the clearing racks. However, it is conventional to provide means to disable clearing of the righthand orders of the register, even though the clearing bar 19 is operated by power. This result can be secured by rotating the knob 17 so as to move the interponent 20 to a disconnecting position. In this position, operation of the bar 19 is ineffective to move the knob 17 and the connected slide 125, although the bellcrank 31 and the stop slide 25 will be operated as heretofore described.

The slide 125 is provided with ordinally arranged pins, or studs, 128 which are embraced within slots 129 formed in the forward ends of the operating bars 109. Thus, the reciprocation of the slide 125 will rock the arms 1% (first counter-clockwise during the clearing stroke, and then clockwise on the return stroke of the clearing mechanism) The operating arms 100 have no effect upon the dials 11- during the first movement (the counter-clockwise movement, which occurs when the clearing bars 15 move tothe right to clear the register). At the end of such stroke,

the arms 100 will lie as far to the right of their associated pins 77 as they are shown to the left thereof in Fig. 1 (which shows the normal, or inoperative, position of the clearing mechanism). About halfway through the return stroke, the shoulder 99 on those operating arms 10% which are permitted to lie in their forward position will engage the pin 77 on the related dial, thereby rocking the dial slightly so that its associated clearing gear 16 will be rotated to mesh with the rack 15 on the balance of the return stroke of the rack. By this means, the dials are returnedto the 5, or half-cent, positon shown in the first order of Fig. 1. It might be mentioned that the mounting of the arms 100 above-described enables an arm to yield to the rear in the event the related dial lies in. such a position that the pin 77 will engage the forward end of the arm 100 upon the first, or rightward, stroke of the. clearing mechanism.

Preferably, means are provided for blocking overthrow of the dials as they are rotated from the 0 to the 5 position on the return stroke of the clearing rack 15. A simple stopping mechanism is shown in Fig. 2 and comprises a second, or auxiliary, stop slide 79 mounted on the top of the frame bar, preferably above the first mentioned, or conventional, slide 25. Preferably, this auxiliary slide 79 will be provided with slots 23, which likewise embrace the studys 24 rigidly mounted on the top of the frame bar 10, whereby both slides can be translated longitudinally, simultaneously, although in opposite directions. The second, or auxiliary, stop slide will likewise be provided with stop fingers 89, which, when the slide is translated to the left, will move into a position to block counter-clockwise rotation of the dial shafts 12. Coopcrating with the stop fingers 89, are stop cams 78 (Fig. 7), similar in shape to the stop cams 27, but mounted on the shafts 12 in an opposite direction, so that while the earns 27 and the related stop fingers 26 prevent clockwise rotation of the dial shafts in a clockwise direction beyond the 0 position, the stop cams 7 8 and their associated fingers 89 block counter-clockwise rotation of the dials in the 5 position. In the embodiment shown in Fig. 2, the abutments on the two cams 27 and 73 lie in the same angular position, but facing in opposite directions, the conventional cam 27 abutting its stop finger 2 6 in the 0 position, while the auxiliary slide will engage the abutment of cam 78 in the diametrically opposed, or number 5, position.

A simple means for operating the auxiliary slide 79 simultaneously with the conventional slide 25, but in the opposite direction, is shown in Fig. 2. The mechanism there shown comprises a two-armed lever 80 rotatably mounted on the left end of the frame bar 10 by any suitable means, such as screw stud 81. The rear end of the lever 80 is provided with a slot 83 which embraces a pin 82 on the stop slide 25. The forward end of the lever I 80 carries pin 84 which abuts against the edge 85 of a projecting arm 86 formed on the left end of the auxiliary stop slide 79. The stop slide 79 is resiliently connected to the'lever 80, as by means of a spring 87 tensioned between the stud 84 on the lever 80 and an car 88 on the projection 86 of the auxiliary slide 79. It is obvious that as the conventional stop slide 25 moves to the right at the start of a clearing operation, the lever 80 will rock in a clockwise direction, whereby its forward end will pull the auxiliary stop slide 79 to the left through the resilient force of spring 87. It should be noted that the connection between the two slides must be, resilient, as the auxiliary stop slide 79 is moved into operative position at the start of a clearing operation and will therefore lie in the path of travel of the abutment on its related cam 78 as the latter rotates in a clockwise direction as the dials are cleared to 0. However, in that condition, the back of the abutment on the cams 78 will cam the auxiliary stop slide 79 to the right. However, this slide is not operative to block rotation of the dial shafts in the 5 or half-cent position until the return stroke of the clearing mechanism, so that such camming of the slide 79 to the right, at this stage of the clearing operation, is immaterial. However, when the return stroke of the clearing mechanism begins, the auxiliary stop slide 79 will be in blocking position, and in that event, the counter-clockwise rotation of the cams 78 will, when the abutments 9i engage the fingers 89 thereon, block operation of the shaft, but will not cam the slide 79 to an inoperative position.

, From the description of the mechanism given above, it is believed obvious that a 5, or other predetermined value, can be inserted automatically in any selected order of the register dials 11, without causing the dial to go through the tens-transfer, or 9 to 0, position of the dial. The operator merely has to lift the knob sufiicient to free it from the stud 116 and rotate it through an angle of approximately 180, and then allow the knob to reseat on the stud. If preferred, the knobs 110 can be provided with indicating indicia on opposing sides thereof to indicate the position of the mechanism, such as a on the shaft of the knob above the cam 113 and a 0 on the opposite side. If the cam 113 lies to' the rear, it will engage the stud 114 on the operating arm 100 associated therewith, thereby camming the arm rearwardly. In this position, the rocking, or oscillation, of the arm will be ineffective to engage the pin 77 on the ordinally related dial and will therefore leave the dial in the 0 position to which it has been returned in the clearing operation." On the other hand, if the operator desires a half-cent, or 5, inserted in that order, the knob is rotated so that the cam lies forwardly, as shown in the first order of Fig. 1. In that condition, the arm 100 is resiliently biased forwardly, so that in the return stroke of its oscillatory movement its shoulder 99 will engage the pin 77 and thus rock the dial shaft 12 so that the mutilated gear 16 thereon will engage the associated rack 15 for the balance of the return movement of the rack.

I claim:

1. In a calculating machine having a carriage frame, rotatable register dials mounted in said frame, and reciprocable means for clearing said dials to their 0 positions during movement in one direction and normally disengaged from said dials during movement in the reverse direction, the combination which comprises a projection on a preselected dial, an arm pivotally mounted on said carriage frame, means operated by said reciprocable means for rocking said arm in synchronism therewith and so constructed as to cause said arm to engage said projection at a predetermined point in the reverse movement of said reciprocable means and thereby engage the preselected dial with said reciprocable means for reverse operation thereby, and means for blocking rotation of said dial during such reverse operation beyond a preselected value position.

2. In a calculating machine having a carriage, a plurality of rotatable register dials mounted in said carriage, and selectively operable means for rotating said register dials to a 0 position, said means including a multilated gear connected to each dial and a reciprocable member mounted in said carriage and movable in one direction to engage said gears and effect such rotation to the 0 position and in a reverse direction to return idly to its original position, a projection on selected ones of said dials, arms pivotally mounted on said carriage and operable by said reciprocable member at a predetermined point in its reverse movement to engage the projections on their respective dials and thereby rotate said dials in a reverse direction sufiicient to cause said reciprocable member to engage the gears connected to said dials, means for adjusting the said arms on their respective mountings toward or away from engagement with the projection on their respective dials, and means elfective during such reverse rotation for blocking rotation of said dial beyond a preselected value position.

3. In a calculating machine having to carriage including a frame, a register including rotatable dials mounted in said carriage frame, and a clearing mechanism for such register which includes a mutilated gear connected to each such dial for rotation therewith, a reciprocable rack slidabiy mounted in said frame for rotating said mutilated gears to a 0 position during movement of said raclt in one direction and normally disengaged from said gears during movement in the opposite direction. astop member operated by said rack for stopping said dials in a 0 position, and means for operating said rack, the combination with said clearing mechanism which comprises a projection on selected ones of said dials, arms pivotally mounted on said carriage frame for oscillation in paths adapted to engage the projections when the dials are in their 0 positions, means operated by said rack for oscillating said arms whereby said arms engage said projections ata predetermined point during the movement of said rack in the opposite direction to rotate said gears into mesh with said rack, a yieldable stop member operated by said stop member and operative during movement of the rack in the opposite direction for blocking rotation of said gear and dial beyond a preselected angular position during such return stroke, and means for severally adjusting the pivotal mounting of said arms toward or away-from their respective dials.

4. A resetting mechanism for a calculating machine register having a plurality of rotatable dials which comprises a mutilated gear connected to each such dial for rotation therewith, a reciprocable rack for rotating said mutilated 'gears to a 0 position during movement in one direction and normally disengaged from said gears during movement in the opposite direction, means for operating said rack, an oscillatable arm cooperating with a selected dial, a fulcrum for said arm fixed withrespect to said dial, means operated by said rack for oscillating said arm, means aflixed to said selected dial for engaging said arm at a predetermined point in the movement of said rack in the opposite direction to rotate the said mutilated gear of the said selected dial into mesh with said rack, means for disabling the arm from engaging the means aflixed to the dial and means for blocking rotation of said gear beyond a preselected angular position during such movement of the rack in the opposite direction.

5. A resetting mechanism for a calculating machine register having a plurality of rotatable dials which comprises a mutilated gear connected to each such dial for rotation therewith, a reciprocable rack for rotating said mutilated gears to a 0 position during movement of the rack in one direction and normally disengaged from said gears during movement in the opposite direction, and means for reciprocating said rack, projections on selected dials, operating arms cooperating with the selected dials, said arms being fulcrumed on pivots fixed with respect to said dials and adapted to engage said projections at a predetermined point in the movement of said rack in the opposite direction, means for rocking said arms in synchronism with said rack, whereby the dials and clearing gears are rotated to engage the teeth of said clearing rack during the balance of said movement in the opposite direction, and means for positioning said arms on said fulcrums in an operative or an inoperative position with respect to said projections on said dials.

6. In a resetting mechanism for a calculating machine register having a plurality of rotatable dials which includes a mutilated gear connected to each such dial for rotation therewith, a reciprocable rack for rotating said mutilated gears to a 0 position during movement of the rack in one direction and normally disengaged from said gears during movement in the opposite direction, and means for operating said rack, the combination comprising projections on selected ones of said dials, operating levers cooperating with selected ones of said dials and operated by said reciprocating rack, said arms being pivotally mounted on fulcrums fixed with respect to said dials and adapted to engage said arms at a predetermined point in the movement of said rack in the opposite direction for rotating such selected dials to engage the teeth of said rack during the balance of said movement in the opposite direction, means for positioning said arms on said fulcrums in an operative or an inoperative position with respect to saiddials, and means for blocking rotation of said dials beyond a predetermined angular position during movement of the rack in the opposite direction.

7. In combination in a calculating machine having a carriage, rotatable register dials mounted in said car riage, and. reciprocable means for clearing said dials to their '1) positions during movement in one direction and normally disengaged from said dials during movement in the reverse direction: a lever pivotally mounted on said carriage, means for adjusting the said lever on its mounting toward or away from engagement with a respective dial, means connecting said lever to said reciprocable means for operation therewith and so arranged that said lever may engage the respective dial at a predetermined point in the reverse movement of said reciprocable means, whereby the dial is rocked into engagement with the reciprocable means and then rotated by said reciprocable means in a reverse direction away from 0 during the balance of the movement of said reciprocable means in a reverse direction.

References Cited in the file of this patent UNITED STATES PATENTS Brown May 30, Brown Oct. 3, Enders Mar. 7, Dreher Sept. 10, Pott Jan. 7, Ferry Feb. 24, Moody Nov. 16, Chall Nov. 24,

FOREIGN PATENTS Great Britain Nov. 20, 

